Debt

Debt with a contractual term less than one year is generally classified as short-term debt and consisted of the following as of December 31 (in thousands):



	2016		2015
Unsecured commercial paper	$	1,055,708	$	1,201,380
Total short-term debt	$	1,055,708	$	1,201,380

Debt with a contractual term greater than one year is generally classified as long-term debt and consisted of the following as of December 31 (in thousands):



	2016			2015
Secured debt (Note 11)
Asset-backed Canadian commercial paper conduit facility	$	149,338		$	153,839
Asset-backed securitization debt	797,755			1,463,154
Less: unamortized discount and debt issuance costs	(1,480		)	(3,777		)
Total secured debt	945,613			1,613,216

Unsecured notes
3.88% Medium-term notes due in 2016 par value, issued March 2011	—			450,000
2.70% Medium-term notes due in 2017 par value, issued January 2012	400,000			400,000
1.55% Medium-term notes due in 2017 par value, issued November 2014	400,000			400,000
6.80% Medium-term notes due in 2018 par value, issued May 2008	877,488			878,708
2.40% Medium-term notes due in 2019 par value, issued September 2014	600,000			600,000
2.25% Medium-term notes due in 2019 par value, issued January 2016	600,000			—
2.15% Medium-term notes due in 2020 par value, issued February 2015	600,000			600,000
2.85% Medium-term notes due in 2021 par value, issued January 2016	600,000			—
3.50% Senior unsecured notes due in 2025 par value, issued July 2015	450,000			450,000
4.625% Senior unsecured notes due in 2045 par value, issued July 2015	300,000			300,000
Less: unamortized discount and debt issuance costs	(21,242		)	(21,106		)
Gross long-term debt	5,751,859			5,670,818
Less: current portion of long-term debt, net of unamortized discount and issuance costs	(1,084,884		)	(838,349		)
Total long-term debt	$	4,666,975		$	4,832,469

A summary of the Company’s expected principal payments for debt obligations as of December 31, 2016 is as follows (in thousands):



	2017		2018		2019		2020		2021		Thereafter		Total
Principal payments on debt	$	2,145,781	$	1,192,458	$	1,483,236	$	658,814	$	600,000	$	750,000	$	6,830,289

Commercial paper maturities may range up to 365 days from the issuance date. The weighted-average interest rate of outstanding commercial paper balances was 0.93% and 0.56% at December 31, 2016 and 2015, respectively.

In April 2016, the Company entered into a new $765.0 million five-year credit facility to refinance and replace a $675.0 million five-year credit facility that was due to mature in April 2017. The new five-year credit facility matures in April 2021. The Company also has a $675.0 million five-year credit facility which matures in April 2019. The new five-year credit facility and the existing five-year credit facility (together, the Global Credit Facilities) bear interest at variable interest rates, which may be adjusted upward or downward depending on certain criteria, such as credit ratings. The Global Credit Facilities also require the Company to pay a fee based on the average daily unused portion of the aggregate commitments under the Global Credit Facilities. The Global Credit Facilities are committed facilities and primarily used to support the Company's unsecured commercial paper program. During July 2015, the Company borrowed C$20 million under the Global Credit Facilities, and the Company repaid the borrowings in August 2015. No borrowings were outstanding at December 31, 2016 and 2015.

In May 2016, the Company entered into an additional $25.0 million credit facility which expires May 24, 2017. The $25.0 million credit facility bears interest at variable interest rates, and the Company must pay a fee based on the unused portion of the $25.0 million commitment. No borrowings were outstanding as of December 31, 2016.

All of the Company's medium-term notes (collectively, the Notes) provide for semi-annual interest payments and principal due at maturity. At December 31, 2016 and 2015, unamortized discounts and debt issuance costs on the Notes reduced the balance by $12.5 million and $11.8 million, respectively.

During 2016, 2015 and 2014, the Company repurchased an aggregate of $1.2 million, $9.3 million, and $22.6 million, respectively, of its 6.80% medium-term notes which mature in June 2018. As a result, the Company recognized in financial services interest expense $0.1 million, $1.1 million, and $3.9 million of loss on extinguishment of debt, respectively, which included unamortized discounts and fees. During March 2016, $450.0 million of 3.88% medium-term notes matured, and the principal and accrued interest were paid in full. During September 2015, $600.0 million of 1.15% medium-term notes matured, and the principal and accrued interest were paid in full.

The Company's senior unsecured notes provide for semi-annual interest payments and principal due at maturity. The Company used the proceeds from the issuance to repurchase shares of its common stock in 2015. Unamortized discounts and debt issuance costs on the senior unsecured notes at December 31, 2016 and 2015 reduced the balance by $8.7 million and $9.3 million, respectively.

HDFS and the Company are subject to various operating and financial covenants related to the credit facilities and various operating covenants under the Notes and the U.S. and Canadian asset-backed commercial paper conduit facilities. The more significant covenants are described below.

The operating covenants limit the Company’s and HDFS’ ability to:


•	assume or incur certain liens;


•	participate in certain mergers or consolidations; and


•	purchase or hold margin stock.

Under the current financial covenants of the Global Credit Facilities, the consolidated debt to equity ratio of HDFS cannot exceed 10.00 to 1.00 as of the end of any fiscal quarter. In addition, the ratio of the Company's consolidated debt to the Company's consolidated debt and equity, in each case excluding the debt of HDFS and its subsidiaries, cannot exceed 0.70 to 1.00 as of the end of any fiscal quarter. No financial covenants are required under the Notes or the U.S. or Canadian asset-backed commercial paper conduit facilities.

At December 31, 2016 and 2015, HDFS and the Company remained in compliance with all of these covenants.